The quickest and most economical way to perform pneumatic field calibrations on pressure transmitters, switches or gauges using an external pressure calibrator as the reference.
This has been replaced by the DCAP hand pump https://www.ralstoninst.com/pneumatic-scissor-hand-pumps

Pneumatic Scissor Hand Pumps with Gauge Connection

Quick and efficient pneumatic field testing of pressure transmitters, gauges or switches.